I salute your remarkable memory--but calling plagiarism is a risky thing to do--and sometimes results in long and complicated court cases. I see a great many children's books, and very often the same themes, and similar treatments come up. Also, specific reading experiences can lodge in the subconsious, and an artist may innocently repeat something seen a long time ago and not consciously remembered. My own policy is this: If you like a book, write it. Good artists borrow--great artists steal. I have never been a big Margaret Wise Brown fan, and don't remember The Friendly Book, but it would be interesting to compare it side-by-side with And Here's to You, and see which one seems a better work of art.